What a congenial country New Zealand is for visitors from what used to be called "the home country." So far from home but the language is the same and you can buy Marmite and Cadbury's chocolate. The Queen is on the banknotes (although they are made of a non-creasable, washable, transparent plastic) and there is scandal about Prince Edward in "Women's Weekly" which would be considered too racy for even the UK tabloids. It all seems half-familiar with a style of friendliness that is a change from English reserve. I feel very much at home.

I am staying for a few days in Cambridge in the centre of the North Island - close to the thermal jollity of geysers and sulphurous springs and within easy reach of Coromandel peninsula where I paddled in the South Pacific last weekend. The string of Bali Hai's across the green ocean couldn't entice me from my reason for being here, which is to film Gandalf's arrival in Hobbiton at the opening of Peter Jackson's film The Lord of the Rings

We are on location an hour's flight north of the Three Foot Six studios in Wellington. The village has weathered nicely since it was built a year back. The flowers have had a chance to settle in and bloom. Nasturtians, sunflowers, daisies and a fieldful of allotments where communal gardening has produced rows of vegetables and fruit. Hobbiton looks itself, settled-in and cosy. It has been tucked in and around the curving farmland, surrounded by green low peaks and gentle valleys. The lone poplars on the horizon look as if placed by the art department but I'm told were not. You can never be sure. The smoke rising from the domesticated holes where the hobbits live is provided by an oil-burning machine. The front door of Bag End itself, where Gandalf knocked last week, opens onto a space no larger than a film camera needs. The interiors are set up, awaiting our return next week to the Three Foot Six studios in Miramar, Wellington. The produce on sale by the Green Dragon, just across the bridge from the mill with its electrically run wheel, is real enough.

Between each take I watched the billy goat snatch from a stall a real cabbage to chew in the hot sunshine. I was sheltering under the marquee "Video City" where Peter Jackson examines each shot with Victoria Sullivan supervising the script, continuity and accuracy of the text.

On film I am spending my opening days shooting on board the cart laden with fireworks for Bilbo's "long expected party." The novel's title for the first chapter has been slipped into Gandalf's chat with Frodo, who has jumped up beside him. Fun as it is guiding the friendly brown 13-hand high Clyde and bantering with Elijah Wood, most of the time I am nowhere near the camera.

David Brunette (recent graduate in computer design) collects me before dawn and drives me the 30 minutes to the set. By the time the sun is up Rick Findlater (from the Gold Coast in Australia) is half way through my 3-hour makeup, which was designed by Peter Owen. This took three screen tests to perfect.

Peter Jackson has ensured that Tolkien rules the enterprise. So, in working out Gandalf's appearance we went back to the few terse descriptions in the novel. We agreed that the cover illustration of Gandalf on the HarperCollins complete edition of "The Lord of the Rings" had captured too much of our collective imaginings to be ignored. John Howe painted it and he has for 18 months been crucial to the "conceptual art" of the movie, along with that other formidably imaginative illustrator, Alan Lee.

At the first screen test the beard was too long and cumbersome for Gandalf the man of action - he is forever tramping and riding and on the move. I didn't want a beard which hampered me with a life of its own once the winds blew. Alien visages stared back at me from the mirror - hirsute offbeats like Shylock, Fagin, and Ben Gunn. Even Rasputin for a moment.

For the second test, the beard was care-freely slashed by Peter Owen, who hadn't had much confidence in it nor in the whiskers that hid my cheeks. Once he had trimmed it all back, I saw a glimmer of the old wizard's sternness. I smiled and tried a Gandalf twinkle, the friend of the Hobbits who admires their spirit and sociability.

Peter Jackson suggested a droopier moustache. I suddenly looked like a double for the Beatles' Maharishi. So the eyebrows, over-faithful to Tolkien's description, were plucked thinner and shorter. The old guru was still there but you couldn't put a name to him. At last Ngila Dickson placed her pointed, blue/grey Wizard's hat on top. Out of the blue, I remembered the silver scarf that he wears in the book. Somehow it had been overlooked or decided against. Until I looked the part I hadn't missed it either. And there's a thing to ponder - what does a man with an umbrella for a hat and a warm cloak need with a scarf? The book starts in autumn. We are filming in summertime. Weather conditions aside, I thought he might have the silver scarf much as he has the pointy hat - to disguise himself. The Gandalf who visits his old friends Bilbo and Frodo has lots of props. Already I have had to cope with his staff, his toffees, his pipe, as well as Clyde - why not a scarf to do some magic with?

Only when Peter Jackson was certain that Fran (co-screenwriter Frances Walsh), Philippa (co-screenwriter Philippa Boyens), Alan Lee, Peter Owen, and I liked what peered back at us through the various applications, did he give his own approval. He's a director who likes to share decision making. It's a large crew and cast but we are all encouraged to contribute.

It's very impressive how New Line supports such an eccentric enterprise. I haven't been here long enough to judge whether Peter is a national hero but he should be up there with Sir Edmund Hillary for his enterprise. Apart from the artistic audacity, he is bringing employment and international attention to his country. He says of his Everest that it's the biggest film ever made technically and logistically. He is not so foolhardy as to think he could ever make these three films by himself. We are all on his team.

They had been filming without me for three months and I felt like the new boy at school as they re-grouped two weeks into the year. Term started with a rough cut of the action so far - those that didn't need major special effects added. A videotape was projected onto the screen of the cinema near the WETA workshops where the dailies are viewed. The soundtrack was uneven. The music was from other movies. And so the audience began by cheering their hard work like a home movie until the story took over and through the silence they watched Boromir die and the hobbits weep as they lose Gandalf to the Balrog. Peter had provided beer and wine but I'm off the alcohol and had two candy floss (cotton candy) and popcorn. Then a party at the house of Barrie Osborne (Producer) and his partner Carol Kim (Production Manager.) At the end of the evening Billy Boyd ("Pippin") persuaded me to follow him down the fireman's pole that falls twenty feet to the hall. And I wasn't even drunk.

Two more days in Hobbiton - the forecast is for sunshine which will sparkle on my silver scarf.